Hydraulic control valve systems and methods

ABSTRACT

A subsea control valve is described having an improved hydraulic actuation system for movement of the gate and shear seal. The described valve also features a pressure monitoring arrangement for sensing pressure within portions of the valve. In a second described aspect, a control valve is provided with a segmented solenoid core actuator that allows for more certain actuation of the valve. In a further aspect, a valve system is described having a manifold with an improved fluid distribution system. In a further aspect, an exemplary valve is described having a pair of solenoid actuation coils. In still a further aspect, a solenoid actuated valve is provided with pulse-type actuation.

This application is a continuation-in-part of U.S. patent application Ser. No. 10/382,254 filed Mar. 5, 2003.

FIELD OF THE INVENTION

The invention relates generally to control valves. In more specific aspects, the invention relates to control valves useful in remote locations where long signal lines are required, such as is the case with submerged Christmas trees used with subsea oil production; and methods for assembling and using the control valves.

DESCRIPTION OF THE RELATED ART

Due to cost, most subsea oil and gas wells are produced to, and controlled from, an available offshore host facility. Rarely are new offshore structures constructed unless they are dedicated to several wells. Each well, in most cases, can be miles away from the facility. Control of the wells on such long offsets has been performed using several different methods: direct hydraulic, piloted hydraulic, direct electric, and multiplex electric, just to name a few. In the direct hydraulic method, valves, such as subsea tree valves, are controlled using individual pressurized conduits from the surface hydraulic power unit (“HPU”). This method can be used over a short offset but is prohibitive over a longer distance due to the slow response time to open or close a subsea valve. It is also typically limited to control only one or two wells due to the number of conduits required to control each tree. In the piloted hydraulic methodology, control valves are placed locally on the subsea tree and then pilot operated from the surface HPU as to direct a main hydraulic supply to the individual tree valve actuators. This method has a shorter response time due to the fact the hydraulic conduits from the host facility only need to actuate the smaller pilot valves and not the larger tree valves. Although operational distance has been increased using the “piloted hydraulic” method operation of more than a few wells, it is still prohibitive by the number and size of the pressure conduits required in the control link umbilical.

In the direct electric methodology, control valves are placed locally on the subsea tree which are then operated selectively using electrical power from the host facility. Individual conductor sets are dedicated to each valve. The subsea control valves can be operated selectively by a simple switch or Program Logic Controller (“PLC”). In addition the PLC can be mounted on and used for control of the HPU, thus increasing the system efficiency. The problem of extended distances are somewhat solved with this method. However, use of the direct electric methodology for more than a few wells is still prohibitive by the number and size of the electrical conductors required in the control link umbilical.

In the multiplex methodology, control valves are placed locally on the subsea tree then operated selectively using an electrical power and signal link from the host facility. The electrical power is sent to the valves, which are then selected for operation by a signal via modem. The number of pressured conduits and electrical conductors are greatly reduced in the control umbilical link to the subsea trees. Many aspects of distance and multi-well control are solved with this method. However, there still exists a need for a control valve system operated over long distances and placed locally, for example, on a subsea tree, operated selectively using electrical power from the host facility and which uses a minimal number of conduits and a minimal amount of power.

The electrically operated control valve may have several configurations depending upon the specific application. The following are a few examples of configurations that may be used. These include a “power on activated” methodology, a pulse activated methodology, and a failsafe methodology. In the power on activated methodology, the valve will remain open or activated as long as electrical power is applied to an electrical power actuator such as a solenoid coil. When the power is removed the valve will close or deactivate. In the pulse activated methodology, an electrical power pulse is applied to the solenoid and the valve remains in the activated position until the solenoid is pulsed again to close or deactivate. Constant electrical power is not required to maintain the valve in the activated position due to a mechanical or hydraulic detent which keeps the valve in the last position. In the fail-safe methodology, the valve is pulse activated and will remain open until the supply pressure drops below a specific value or the solenoid is pulsed again. This type of valve is typically used in conjunction with the pulse activated last position type valve as a fail-safe measure. The failsafe portion of the valve is placed upstream of the pulse activating portion of the valve in order to cut off pressure to all functions and block the supply until reactivated. The fail-safe type valve is not usually configured with a coupler outlet interface because it only communicates via the supply line internal the valve module.

The electric power required to operate an electrically-powered actuator for a valve, such as a solenoid valve, is a function of the square of the force required and, therefore, any reduction in the force required to operate the valve will afford significant economics in both the construction and the operation of a solenoid actuated pilot valve. For example, if the force to operate a valve is cut in half, the power consumption is thereby reduced to one-fourth the original amount. A sizable savings by reducing the amount of power required to move a solenoid plunger, both from the standpoint of the cost of the initial installation, subsequent operating cost, and reduced heat build-up which provides for greater reliability. Recognized is the need for a control valve requiring minimal amount of electrical power to be actuated.

The state-of-the-art has found shear-type valves to be highly effective in controlling hydraulic functions such as functions on a sub sea tree. The typical shear-type valve will have at least two opposing shear seals communicating with each other through the gate. One will remain covering the supply port during actuation with the other shuttling from block to covering the function port. This allows the supply pressure to access the function upon actuation. On deactivation the supply pressure is again blocked with the function uncovered and venting inside the valve cavity and vent port. The inherent problem with this configuration is shear seal sliding friction which is induced by the hydraulic pressure. The shear seals must be relatively large in order to cover the supply port in both the actuated and inactivated position. The radial seal around the shear seal encircles a large area which is acted upon by the hydraulic pressure. The net result is high force generated on the shear seal face (multiplied by two) that can require high solenoid force to slide from one position to the other. Several solutions have been derived in the past to combat the result of high seal friction. One solution was to add secondary hydraulic pilots to each valve that move the gate from one position to the other. Another solution was to make the porting in the shear seals very small, so the overall net force on the face is manageable. Yet another solution was to incorporate a very large electrical coil to move the gate. And yet another solution, was a combination of some or all of the above. All of the noted solutions have their own inherent problems which for the most part increase the size and complexity of the whole subsea system, reduce or restrict the flow to the subsea function or both. Thus, there is a need for compact, less complex, control valves requiring a minimal amount of power to be actuated.

A typical subsea control valve does not contain or have the means to connect directly to the function coupler mounted on a base structure, such as those on a sub sea tree. Typically, this entails using a separate male and female coupler. The associated female coupler is an independent component that is either mounted on the bottom of the removable module or assembled on to the valve using a threaded connection with an o-ring seal. The coupler serves only as a hydraulic connection with the mating male coupler on a module fixed base. These subsea hydraulic couplings are well known in the art. Typically, the couplings consist of a male end and a female end with sealed fluid passageways therebetween. The female coupler typically includes a cylindrical body with a relatively large diameter receiving chamber for slidably engaging the male coupler and a relatively small diameter longitudinal bore at the other end. The small bore facilitates connections to hydraulic lines, while the larger bore seals and slidingly engages the male coupler. The male coupler typically includes a cylindrical portion at one end having an outer diameter approximately equal to the diameter of the receiving chamber in the female coupler. The male coupler also typically includes a connection at its other end to facilitate connection to hydraulic lines. When the male coupler is inserted into the receiving chamber of the female coupler, fluid flow is established between the male and female couplers.

The typical coupling devices include the ability to arrest fluid flow when not in mutual contact. The male and female couplers typically include a poppet valve within a central bore of each coupler. Each poppet valve typically includes a conical valve seal which seats, in the closed position, against a valve seat in the bore of each coupler. The poppet valve is engaged by the opposing coupler's valve actuator and opens to allow fluid flow. The poppet valve closes to arrest fluid flow against a valve seat within the bore. Typically, the poppet valve is spring-biased to the closed position. The valve actuator typically includes a nose or stem extending from the apex of the valve seal along the longitudinal axis of the poppet valve. Engagement between the valve actuators of the male and female coupler's poppet valves forces each valve face away from the valve seat and into the open position for fluid flow between the couplers. Additional coupling devices typically, the male couplers and female couplers, are attached to opposing manifold plates, whereby in emergency situations, the manifold plate can be quickly separated from the sub sea function, a subsea tree, for example, disconnecting the male and female couplers. Having both male and female couplers as separate units adds to the complexity and size of the valve module. Recognized is that eliminating the need for hydraulic conduit or passageways from the valve to the hydraulic coupler can result in reduced costs and complexity, increased reliability because as many as two seals per circuit can be eliminated by combining the two components into one. There exists, therefore, the need for a coupling assembly that is integral with or part of the control valve.

The typical subsea control valve arrangement includes some form of external valve packaging. The most prevalent packaging methodology includes, but is not limited to, some basic options such as: the controlled environment, and the non-controlled environment. In the controlled environment, the valve is typically enclosed in a dielectric fluid filled chamber or module which is typically pressure compensated to mirror that of the surrounding sea water head. A typical subsea control valve is fully enclosed in this chamber and communicates hydraulically to the subsea function via conduit passages to an external mounted hydraulic coupler. The improved valve extends outward from the chamber to directly contact and communicate with the male couplers on the fixed base and will have an environmental seal to separate the chambered fluid from the sea water. It is common for both the hydraulic supply and vent to be routed to a manifold in this configuration. In the non-controlled environment, the valve housing is typically in direct contact with the sea water. The electronics are accessed using conductors placed in a fluid filled hose which in turn typically pressure compensates the electronics section of the valve. No chamber environment seal is required for this configuration. It is common to vent the hydraulic fluid inside the module in this configuration.

A typical control valve will also have an external port tapped into the function output where an independent pressure switch or pressure transmitter is installed at the module assembly. The switch or transmitter may also be threaded and sealed onto the function passage of a manifold between the valve and the output coupler. This configuration is adequate for a controlled environment as previously described; however, it is not adequate for the non-controlled environment where sea water is in direct contact with the module components. Because of the switch location, a second fluid filled hose must be used to protect all of the conductors, one for the solenoid coil, and one for the pressure switch or transmitter. In a module that contains several valves the complexity and cost of two fluid filled hoses per valve may be prohibitive. Recognized, therefore, is the need to place the pressure transmitter conductors coincident with the solenoid conductors. Correspondingly, recognized is the need to route all conductors through a single fitting and into a single pressure compensated, fluid filled hose to the module electrical interface.

The parent application to this one, U.S. Patent Application Publication No. 2004-0173268, described an improved hydraulic subsea control valve having a solenoid assembly for actuation of the valve. This application, which is incorporated herein by reference, teaches significant improvements over the prior art. However, further improvement is desirable. In some aspects, the present invention is directed to improved valve arrangements that permit “non-interflow” operation, meaning that, during actuation, there is no point at which both the supply fluid port and the vent port are partially open at the same time. In other words, one of the ports is fully closed off by the shear seal before the other is opened. As alluded to previously, non-interflow valves require the shear seal and associated components to be moved a longer distance within the valve to compensate for the wall thickness of the shear seal. The wall thickness of the shear seal must be at least equal to the distance between the supply and vent ports. Actuation of these types of valves with conventional solenoid acuators is problematic due to the long component travel distance. It is well known the magnetic attraction between components is greatly reduced as the distance between the components increases. Because subsea valves are located well below the surface of the sea (often as much as a mile below), it is impractical to utilize a valve that is prone to failure. The costs of recovery and repair of the valve are prohibitive. Thus, reliable valves are highly desirable.

A related problem of the prior art is the cost and complexity of the manifolds that house multiple subsea valves. Conventional valve manifold assemblies are expensive due to the number of hoses and fluid conduits that are needed to control all of the valves integrated into the manifold. Because supply fluid and vented fluid must be routed to and from each valve, there are a significant number of such conduits and associated fittings to install. Further, numerous ports must be drilled through the housing of the manifold to create the manifold in a time-consuming process. Further, the numerous hoses and conduits are prone to damage during installation or use, resulting in leakage of fluid that is necessary for proper valve operation.

A further problem of prior art valve assemblies is that of assuring that a valve will remain in a desired position during a power outage. For example, if a conventional valve has been opened by a solenoid actuator, a loss of power to the solenoid might result in the valve being closed, when it is actually desired that the valve continue to remain open.

SUMMARY OF THE INVENTION

The present invention is directed to a number of further improvements relating to control valves and control valve manifolds and systems. In one aspect of the present invention, a control valve is described having an improved hydraulic actuation system for movement of the gate and shear seal. The described valve also features a pressure monitoring arrangement for sensing pressure within portions of the valve. In a second described aspect, a control valve is provided with a segmented solenoid core actuator that allows for more certain actuation of the valve. In a further aspect of the present invention, a valve system is described having a manifold with an improved fluid distribution system. In a further aspect of the present invention, an exemplary valve is described having a pair of solenoid actuation coils. In still a further aspect of the invention, a solenoid actuated valve is provided with pulse-type actuation.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of the invention, as well as others which will become apparent, may be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the drawings illustrate only various embodiments of the invention and are therefore not to be considered limiting of the invention's scope as it may include other effective embodiments as well.

FIG. 1 is a partial cross-sectional view of a control valve;

FIG. 2 is a partial cross-sectional view of a control valve taken along line 2-2 of FIG. 1;

FIG. 3 is a partial cross-sectional view of a control valve according to an alternative embodiment shown in FIG. 2;

FIG. 4A is a partial cross-sectional view of the control valve depicting the vent closed-supply open shear seal position according to an embodiment of the present invention;

FIG. 4B is a partial cross-sectional view of the control valve depicting the vent open-supply closed shear seal position according to an embodiment of the present invention;

FIG. 5 is a partial cross-sectional view of the control valve according to an embodiment of the present invention taken along line 5-5 of FIG. 1; and

FIG. 6 is a schematic view of a control valve system according to an embodiment of the present invention.

FIG. 7 is a side, cross-sectional view of an exemplary subsea control valve having a hydraulic actuation system, in accordance with the present invention.

FIG. 7A is an enlarged view of portions of the control valve shown in FIG. 7.

FIG. 8 is a side, cross-sectional view of an exemplary subsea control valve having a segmented solenoid core actuation arrangement, in accordance with the present invention.

FIG. 8A is a side cross-sectional view of the valve shown in FIG. 8 with the valve now in an actuated position.

FIG. 9 is a plan view of an exemplary manfold system for a number of valves, in accordance with the present invention.

FIG. 9A is a cross-sectional view taken along lines 9A-9A in FIG. 9.

FIGS. 9B and 9C are cross-section views taken along lines 9B-9B and 9C-9C, respectively, in FIG. 9.

FIG. 10 is a side, cross-sectional view of an exemplary valve having a locking shuttle in accordance with the present invention.

FIG. 10A is a side, cross-sectional view of the valve shown in FIG. 10, now in an initial open position.

FIG. 10B is a side, cross-sectional view of the valve shown in FIG. 10, now in a third position.

FIG. 10C is a side, cross-sectional view of the valve shown in FIG. 10, now in a fourth position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more fully hereinafter with reference to the accompanying drawings which illustrate preferred embodiments of the invention. Like reference numbers refer to like elements throughout. The prime notation to reference numbers, if used, indicates similar elements in alternative embodiments.

FIGS. 1-5 depict a hydraulic control valve 20 having a valve body 21. As shown in FIGS. 1 and 2, the body 21 has a function port 26 which fluidly interfaces with the hydraulic functions, a supply port 22 to allow for the supply of fluid to the function port 26, and a vent port 23 to allow fluid to vent from the function port 26. The hydraulic control valve 20 also includes a valve actuation assembly 60. As best shown in FIGS. 4A and 4B, the valve actuation assembly 60 includes a plunger, or piston rod, 61 for moving a gate assembly 170 between a supply port blocked position as shown in FIG. 4A, and a vent port blocked position as shown in FIG. 4B. The hydraulic control valve gate assembly 170 includes a gate 171. The gate 171 slidably interfaces with a seal assembly 140. The seal assembly 140 includes a seal carrier 141 slidably mounted within the gate 171 and a shear seal 142 to selectively direct hydraulic pressure to and from a function, such as a subsea function, by selectively alternating between a vent port unblocked-supply blocked position as shown in FIG. 4A and a vent port blocked-supply unblocked position as shown in FIG. 4B. The shear seal 142 is slidably mounted within the seal carrier 141. The illustrated configuration only includes one shear seal 142 for sealing of the supply port 22 and the vent port 23. Using only one shear seal 142 results in relatively low power requirements needed to move the shear seal 142. The relatively low power requirement makes the control valve 20 particularly suitable for remote installation, for example on offshore submerged wellheads and the like.

Still with reference to FIGS. 2, 4A and 4B, the seal assembly 140 also includes at least one, and preferably two, seal carrier return springs 143. The seal carrier return springs 143, spring bias the seal carrier 141 with respect to the gate 171. The gate assembly 170 of the hydraulic control valve 20 also includes a roller bearings assembly 172 having a roller bearing engagement plate 173 and an array of roller bearings 174 in rolling contact, or interface, with the roller bearing engagement plate 173.

The hydraulic control valve 20 further includes a valve actuation assembly housing 41 enclosing the valve actuation assembly 60, a pressure housing 42 enclosing the seal assembly 140; and a spring housing 43 enclosing a gate return spring assembly 100 and a function coupler interface assembly 200. As best shown in FIGS. 2-3, the hydraulic control valve 20 further includes a hydraulic pressure coupling assembly 110 having a seal disk 111 hydraulically connected to hydraulic lines 112.

The hydraulic control valve 20 further includes an internal valve cavity 27 used as both a pressure and a vent chamber, depending on the valve position. In an embodiment, the control valve 20 also includes a pressure switch, or transmitter, 150 integral to the valve and in hydraulic communication with the internal valve cavity 27. The hydraulic control valve 20 includes a conductor aperture 156 which allows conductors 62, 152 to exit the valve body, and a conductor arrangement wherein the position of the pressure transmitter allows for routing electrically conductive pressure switch, or transmitter, conductors 152 and electrically conductive actuating conductors 62 through the same conductor aperture 156. Due to the adjacent position of the coil and pressure switch or transmitter it is possible to gang both units to a single positive conductor with each retaining a separate negative conductor reducing the total conductor count from four (4) to three (3) minimum.

As best shown in FIGS. 2, 3, 4A and 4B, the hydraulic control valve 20 further includes a gate return spring assembly 100. The gate return spring assembly 100 includes a gate return spring 101 having a proximal end 102, a distal end 103, and a spring adapter 104. The gate return spring 101 is disposed in the spring housing 43, with the spring adapter 104 disposed on the proximal end 102 of spring 101. The spring adapter 104 is upwardly biased by gate return spring 101, whereby the gate return spring assembly 100 returns the gate 171 to the vent open-supply blocked position as shown in FIG. 4A when the valve actuating assembly 60 is not energized, as shown in FIG. 4A.

As best shown in FIGS. 2-3, the hydraulic control valve 20 further includes the function coupler interface assembly 200 formed integral with the control valve 20. The function coupler interface assembly 200 includes a female mating hydraulic coupler assembly 201 for matingly connecting with a male coupling associated with the fixed module base B (FIG. 6). Additionally, in a controlled environment embodiment, the hydraulic control valve 20 further comprises an environmental seal 58 positioned to seal between the spring housing 43 and a mounting module or manifold 45. The hydraulic control valve 20 also further includes a valve retainer 46, (such as a retainer nut 46′, ring or weld) for connecting the control valve 20 to the mounting module or manifold 45.

As best shown in FIGS. 2-4, the valve actuation assembly 60 is housed within a bore, or valve actuator chamber 63, of the valve actuation assembly housing 41. The valve actuation assembly 60 includes a plunger, or piston rod 61, for moving the gate assembly 170 between the supply port blocked position as shown in FIG. 4A to a vent port blocked position as shown in FIG. 4B, by engaging an upper surface, or end 175, of the gate assembly 170. In the preferred embodiment, the plunger, or piston rod 61, is slidably positioned within a bore, or plunger chamber 64 of a tube body 65 made of non-magnetic material. The tube has a proximal end 66 and a distal end 67. In the preferred embodiment, the distal end 67 is welded to the proximal end 47 of the pressure housing 42, however, other engagement methodologies as known by those skilled in the art including, threading, are possible. In the preferred embodiment, the distal end 67 also lands within a proximal bore 48 of the pressure housing 42.

In the preferred embodiment, the valve actuation assembly 60 also includes a coil 68 located within the valve actuator chamber 63. The coil 68 surrounds the tube 65 in order to magnetically reposition the plunger, or piston rod 61, to its most distal position when the coil 68 is energized as shown in FIGS. 2 and 4B. The coil 68 preferably lands its distal end 69 upon an annular shoulder 70. In the preferred embodiment, the shoulder 70 is formed by the proximal face of the pressure housing 47. The coil 68 is further retained by an at least one retainer cover 80 preferably formed of a plastic material, although other suitable materials may be used. In the preferred embodiment, the retainer cover 80 has at least one, or as many as are desired, conduits 71 allowing coil actuating conductors 62 to pass through the retainer cover 80. The retaining cover 80 and the proximal portion 66 of the tube 65, in a press fit with are fixedly secured via a bushing 74 and a retaining ring 75 preferably surrounding the outer circumference of the proximal end 66 of the tube 65 in a press fit with retaining cover 69.

As best shown in FIGS. 2-3, the proximal end 66 of the tube 65 includes a bore, or pressure transmitter chamber, 76 not necessarily the same diameter as the bore 64 surrounding the plunger or piston 61. This provides a proximal stop for the plunger or piston rod 61. The proximal end 66 of the tube 65, may be a unitary unit with the body of the tube 65 or may be a separate component. The proximal end 66 of the tube 65 engages a cap 77. The cap 77 is threadingly engaged with, and sealed to, the outer circumference of the pressure transmitter chamber 76 of the proximal end 66 of the tube 65. The cap 77 forms a seal, in this embodiment formed with a spot face O-ring 78, with the inner circumference of the proximal end 66 of the tube 65. Alternatively, the cap 77 may be threaded to the external portion of the tube 65 or welded on either internal or external portions. In an alternative embodiment, the cap 77 is in the form of an epoxy bead. A pressure switch, or transmitter 150, is located adjacent the distal portion 154 of the cap 77. The cap 77 includes a conduit 151 which allows the pressure switch or transmitter conductors 152 to pass through the cap 77. A small cavity 155 is formed between the pressure switch, or transmitter 150, and the proximal end 79 of the plunger or piston rod 61, when in its most proximal position. This allows improved hydraulic fluid flow to the proximal end 79 of the plunger or piston rod 61. Because the valve cavity 27 is integral to the function output passage 199, the pressure switch or transmitter 150 may be mounted as described above and provide accurate function pressure readings. The placement of the pressure switch or transmitter 150, as described, allows the pressure or transmitter conductors 152 to exit the hydraulic control valve 20 in the same area as the coil conductors 62. All conductors 62, 152, can be routed to a single conduit fitting 160, 160′. Local placement of the coil 68 and the pressure switch, or transmitter, 150 also allows the use of only three conductors, one positive and two negative, for operation of both units.

The conduit fitting 160, 160′ engages a bore, aperture, or fitting chamber 156 located at the proximal end 81 of the valve actuator housing 41. The fitting is threadedly received and sealed within the conduit fitting chamber using a spot face O-ring 166. Alternatively, the fitting 160, 160′ may be welded. Whether operating in a controlled or non-controlled environment, the preferred configuration of the conduit fitting 160, 160′ includes a conduit 161 which allows the pressure switch or transmitter conductors 152 and coil conductors 62′ to transmit between the proximal end 163 and distal end 164 of the fitting 160, 160′. As best shown in FIG. 3, in a controlled environment placement of the hydraulic control valve 20, the conduit fitting 160, 160′ is preferably uncapped to allow for entry of fluid, for example dielectric fluid, into a chamber 165 formed between the distal portion 164 of the conduit fitting 160, 160′ and the proximal portion 153 of the cap 77 and proximal portion 72 of the retainer cover 80. In a non-controlled environment for the placement of the hydraulic control valve 20, the conduit fitting 160, 160′ is preferably capped. In this embodiment, the proximal end 163 of the fitting 160, 160′ sealingly engages with a fluid filled hose (not shown).

As best shown in FIGS. 4A and 4B, the valve actuator housing 41 has a distal bore, or distal valve actuator housing bore 82. The inner circumference of the distal valve actuator housing bore 82 surrounds and preferably threadedly engages the outer circumference, or perimeter 85, of the proximal end 47 of the pressure housing 42. Also, the most distal portion 83 of the valve actuator housing 41 lands on a shoulder 84 formed at the outermost proximal end of the pressure housing 42. The valve actuator housing 41 sealingly engages the pressure housing 42 via a welded seal 49 or other similar or suitable seal. The pressure housing 42 and valve actuator housing 41 might also be welded, or otherwise attached, as known by those skilled in the art. Although the shape of the housings and assemblies are illustrated as being cylindrical or round, such structures may of course have any other desired cross-sectional configuration, such as square, hexagonal, etc.

As best shown in FIGS. 4A and 4B and 5, the pressure housing 42 includes a bore, or seal disk bore, 113, which sealingly receives a seal disk 111 of a hydraulic pressure coupling assembly 110. The seal disk 111 preferably has a shoulder 114 formed adjacent the seal carrier side of the disk which acts as a stop between itself and the outer surface 115 of the pressure housing 42, when the seal disk 111 is inserted into the seal disk bore 113. A radial seal 116 seals between the outer circumference 117 of the most seal carrier side of the seal disk 111 and the inner circumference 118 of the seal disk bore 113. As best shown in FIG. 5, the pressure housing 42 additionally includes an at least one bore 119, and preferably four bores 119, for receiving a corresponding screws, or bolts 120, to secure the seal disk 111 to the pressure housing 42. Correspondingly, the seal disk 111 has matching bores 121 for such purpose. As best shown in FIGS. 4A, 4B and 5, the seal disk 111 includes at least one bore, or cavity 122, hydraulically connected to a hydraulic supply line or manifold 123 (FIG. 2) and at least one bore or cavity 124 hydraulically connected to a hydraulic vent line or manifold 125 (FIG. 2). The seal carrier side 126 of the seal disk 111 includes supply and vent ports 22, 23. The seal carrier side 126 of the seal disk 111 and the supply and vent ports 22, 23, adjacent the seal carrier side 126 correspondingly interface with the shear seal 142 to preferably form a metallic seal.

As best shown in FIG. 2, in a non-controlled environment embodiment, the seal disk 111 also preferably includes a supply bore, or cavity 122, and a vent bore or cavity 124 which interfaces with a preferably external supply and vent lines 123, 125. As best shown in FIG. 3, in a controlled environment embodiment, the disk seal 111′ also preferably includes a supply and vent bore or cavity 122, 124, which interfaces preferably with a manifold to allow the supply and venting of hydraulic fluid. The disk seal supply and vent bore, or cavity 122, 124, interface with the manifold using a seal sub 127.

The pressure housing 42 may have a distal bore, or distal pressure housing bore, 130 not necessarily having the same circumference as the bore 169 that houses the gate assembly, or gate assembly bore 169, hereinafter described. The inner surface 131 of the distal pressure housing bore 130 surrounds and threadedly engages the outer surface 132 of the proximal end 133 of the spring housing 43. The most distal portion 134 of the outer surface 132 of the pressure housing 42 lands on a shoulder 135 formed adjacent the proximal end 133 of the spring housing 43. The pressure housing 42 sealingly engages the spring housing 43 via an O-ring seal 136 or the like. Alternatively, the pressure housing 42 and spring housing 43 may be welded or otherwise attached as known by those skilled in the art.

As best shown in FIGS. 2, 3, 4A and 4B, the hydraulic control valve 20 further includes a gate return spring assembly 100. The spring housing 43 includes a bore, or spring adapter bore 105 which houses the gate return spring 101 and the spring adapter 104, and provides a retraction point, thereof. The gate return spring 101 is disposed in the spring housing 43. The spring housing 43 includes a bore, or function output passage 199, which interfaces with the spring adapter bore 105 and which allows passage of fluid to the function coupler interface assembly 200. In the preferred embodiment, the spring adapter bore 105 and the function output passage 199 are of differing sizes creating a shoulder 106 at the distal end 107 of the spring adapter bore 105 for landing the distal end 103 of the gate return spring 101. Alternative means known by those skilled in the art may be used to properly secure the gate return spring 101. The spring adapter 104 is connected to the proximal end 102 of the gate return spring 101, and utilized to reposition the gate 171.

With reference to FIGS. 4A and 4B, the outer perimeter, or circumference, 90 of the proximal end 91 of the spring adapter 104 is smaller than the outer perimeter or surface 92 of the body 93 of the spring adapter 104, resulting in a shoulder 94. Functionally, the gate return spring assembly 100 returns the gate assembly 170 to the vent open-supply blocked position as shown in FIG. 4A when the actuating assembly 60 is not energized. In an embodiment, the proximal end 95 of the spring adapter bore 105 has a smaller diameter than that of both the spring adapter bore 105 and the gate assembly bore 169. The smaller diameter of the proximal end 91 of the spring adapter 104 allows the proximal end 91 of the spring adapter 104 to penetrate into the gate assembly bore 169. As will be described later, in the preferred embodiment the spring housing 43 also provides a gate assembly stop 96 when the gate is in the actuated position as shown in FIG. 4B. The spring adapter 104 also preferably includes a bore 97 hydraulically connected to a conduit 98 to increase hydraulic fluid flow into and out of the spring housing portion of the valve cavity 27.

Referring primarily to FIGS. 2 and 3, the hydraulic control valve 20 further includes a function coupler interface assembly 200 integral with the control valve 20. In the preferred embodiment, the function coupler interface assembly 200 is built into the spring housing 43. The function coupler 200 includes a female mating hydraulic coupler assembly 201 for matingly connecting with a male coupling associated with the fixed module base B. The hydraulic control valve 20 implements the function coupler 200 as one that is mechanically opened when in contact with the mating (male) coupler M. This check valve arrangement will limit sea water ingression during installation, or removal, of the valve 20 or valve package or module 221 (shown in FIG. 6). The function coupler 200 having check valve 202 is implemented as follows. The seal housing 43 includes a bore, or conical valve bore 203 used to interface with a conical valve seal 204, a bore, or male coupler bore 205, for receiving a male coupler M, and a conical shaped bore, or mating bore 206, at the distal end 28 of the spring housing 43 to help guide the male coupler M into the male coupler bore 205, all defining a “female” receiving chamber 207. When the male coupler M is inserted into the receiving chamber 207 of the female coupler 201, fluid flow is established between the male and female couplers, M, 201.

The function output passage 199 includes a recess or attachment point 208 for the proximal end 209 of a conical valve spring 210. The conical valve spring 210 lands the conical valve seal 204 on a shoulder or otherwise engagement point 211 at the proximal end 212 of the conical valve bore 203 formed by the differential diameters between the functional output passage 199 and the conical valve bore 203. Thus, the conical valve 204 is spring-biased into the closed position, forming the check valve 202. The conical valve 204 preferably includes an extension 213 which allows the male coupler M to engage the conical valve 204, thus opening or uncapping the proximal end 212 of the conical valve bore 203. Additionally, the male coupler bore 205 includes a recess or a detent 214 which allows for a firm engagement between the male and female couplers M, 201.

As shown in FIGS. 4A and 4B, the pressure housing 42 includes a gate assembly bore 169. The gate assembly 170 includes a gate 171 which can be engaged by the plunger, or piston rod, 61 at its proximal end 175, and which can be engaged by the spring adapter 104 at its distal end 176. The gate 171 has a bore, or seal carrier bore 180, which slidably interfaces with the external surface of the seal carrier 141. The seal carrier 141 correspondingly has a bore, or shear seal bore 144, which, in essence, slidably interfaces with the external surface 145 of the shear seal 142. The illustrated configuration only includes one shear seal 142 for sealing of the supply port 22 and the vent port 23. A radial seal 146 is located between the external surface 145 (outer circumference) of the shear seal 142 and the shear seal bore 144 (inner circumference). The shear seal 142 acts as a cap that blocks the vent port 23 when the plunger or piston rod 61 (valve actuator) is in the actuated position and blocks the supply port 22 when the valve actuator 61 is in the non-actuated position. The shear seal 142 includes a bore, or fluid bore 147, which allows the supply fluid to pressurize the gate 171 and the shear seal 142 and radial seal 146. The thickness of the wall defining the fluid bore 147 is at least equal to the distance between the supply and vent ports 22, 23. In the preferred embodiment, the seal assembly 140 also includes a plurality of seal carrier return springs 143. The seal carrier return springs 143 springingly connect between the seal carrier 141 and the gate 171. In the preferred embodiment, the gate 171 correspondingly includes a plurality of non-axial bores 177 which house the plurality of seal carrier return springs 143.

The seal assembly 140 has a seal disk side 178 and a side, or gate side, 179 opposite the seal disk. A cavity 181 exists between a portion of the gate 171 surrounding the seal carrier bore 180 and the gate side of the seal carrier 141. A conduit 182 exists to increase hydraulic fluid flow into and out of the cavity 181. In the preferred embodiment, the seal carrier return springs 143 expand when the cavity 181 is being pressurized with supply pressure as when the supply port 22 is unblocked, and contract when the supply port 22 is blocked, retracting the seal carrier 141 and minimizing the size of the cavity 181. The seal carrier return springs 143 effectively maintain the gate assembly 170, and thus the roller bearings 174, in the proper position.

The hydraulic control valve also includes a roller bearing assembly 172 having a roller bearing engagement plate 173 and a plurality of roller bearings 174 roll against or which interface with, the roller bearing engagement plate 173. The roller bearings 174 and roller bearing engagement plate 173 are preferably located opposite the seal carrier side of the gate 171. The combination of the bearing 174 and plate 173 allow for smooth longitudinal movement of the gate assembly 170 between the supply open and the vent open positions as shown in FIGS. 4A and 4B. As noted, the proximal end 183 of the gate assembly bore 169 forms an upper stop 186 for the gate assembly 170. The proximal end of the spring housing 108 preferably includes a protuberance 184 which acts as a lower stop 96 for the gate assembly 170. However, any method known by those skilled in the art may be utilized in order to provide a gate assembly stop 96 at the distal end 185 of the gate assembly bore 169.

Functionally, when the valve actuation assembly 60 is energized, the plunger, or piston rod, 61 extends into the gate assembly 170 for moving the gate 171 until it contacts the lower stop 96. At this point, the shear seal 142 is blocking the vent port 23, and supply pressure will flood the interior of the valve 27 pressurizing the subsea function through the female-male coupler interface (female mating hydraulic coupler assembly 201). The shear seal 142 is aligned with the vent port 23, and supply pressure acting on the seal assembly 140 will force both the seal carrier 141 and the shear seal 142 against the seal disk 111 blocking the vent port 23. There is no pressure inside the shear seal 142 so the roller bearings 174 will only receive the force generated by the seal carrier return spring(s) 143.

Correspondingly, when the valve actuation assembly 60 is deenergized, e.g. electrical power removed from the coil 68, the gate return spring 101 will push the gate 171 back to the original position as shown in FIG. 4A. In this position, the gate 171 will contact the upper stop 186. At this point, the shear seal 142 is aligned with the supply port 22. The vent port 23 is now open and the supply port 22 is capped or closed by the shear seal 142. Function pressure will exit the valve 20 through the open vent port 23 and the associated header. In the preferred embodiment, the shear seal 142 also includes a fluid bore, or shear seal transfer channel, 147 preferably having a diameter larger than the diameter of the supply port 22. As shown in FIG. 4B, when the shear seal 142 is blocking the supply port 22, i.e., aligned with the supply port 22, supply port pressure is fed through the shear seal 142 activating the radial seal 146 between the seal carrier 141 and the shear seal 142. Pressure acting on the differential area between the face of the shear seal 142 and the radial seal 146 will contain or block the supply. The supply fluid pressure will form a fluid filled cavity between the gate side of the shear seal 142 and shear seal carrier 141, thus loading the gate 171 back onto the opposing roller bearing assembly 172 and thus improving the seal performance.

A benefit for this configuration, using only one nominal size shear seal 142, is lower sliding friction. In the preferred embodiment, the shear seal face surface net area need not be any greater than approximately 0.075 square inches due to low friction resulting from using only one shear seal 142 The lower friction can then be translated into nominal porting size no greater than an approximately 0.0048 square inch area while still complying with MMS regulations, and nominal solenoid and gate return spring size and thus allow the use of higher working pressures equal to or exceeding 10,000 psi.

The hydraulic control valve 20 includes an internal valve cavity 27 used as both a pressure and a vent chamber, depending on the valve or gate assembly, 170 position. This configuration allows for the mounting of the pressure switch or transmitter 150 adjacent the proximal end 81 of the valve actuator housing 41. Functionally, the pressure switch or transmitter signal can be used to verify the control valve 20 has functioned properly and the desired subsea function has been activated. In an embodiment, the control valve 20 includes such pressure switch or transmitter 150 in hydraulic communication with the internal valve cavity 27, and also preferably placed adjacent the proximal end 81 of the valve actuator housing 41. The placement of the pressure switch or transmitter 150 in this location allows the conductors 152 to exit the control valve 20 in the same local area as the coil conductors 62. All conductors 62, 152, can be routed through a single fitting or aperture 156 and into a single pressure compensated, fluid filled hose (not shown) to the valve electrical interface or in the controlled environment mode, into a pressure compensated mounting module (schematically shown in FIG. 6).

As best shown in FIGS. 2-3, the hydraulic control valve 20 includes a mounting assembly 40 whereby the control valve mounts either to a mounting plate or module 45 in conjunction with a valve retainer 46. The mounting plate 45 includes a bore, or mounting bore, 50 which provides a entryway, preferably slidable, for the control valve spring housing 43. Correspondingly, the hydraulic control valve 20 also further includes the valve retainer 46 (retainer nut, ring or weld) for connecting the control valve 20 to the mounting plate or module 45. The spring housing 43 threadedly interfaces with the valve retainer 46. The proximal side 51 of the valve retainer 46 removably engages with a distal side 54 of the mounting plate or module 45 depending on the environmental configuration. This arrangement forms a distal support for the hydraulic control valve 20. Also, the proximal side of the mounting plate or module 45 engages a mid-section shoulder 55 of seal housing 43 which forms a proximal support (see FIG. 3). The combination of the two supports removably locks the hydraulic control valve 20 to the mounting plate 45.

In the controlled environment of FIG. 3, where the mounting assembly 40 includes a mounting manifold 45′, the mounting manifold 45′ preferably includes a distal bore 50′ sized to receive the control valve outer spring housing 43 below the midsection shoulder 55, and a proximal bore 56 located on the same longitudinal axis as the distal bore 50′ and sized to receive the control valve outer spring housing 43 above the midsection shoulder 55. The transition point between the proximal bore 56 and a distal bore 50′ form a module mid-section shoulder 57. This arrangement forms a proximal support for the hydraulic control valve 20 between itself and the spring housing midsection shoulder 55. As in the non-controlled environment, the hydraulic control valve 20 also further includes a valve retainer 46 (retainer nut, ring or weld) for connecting the control valve 20 to the mounting manifold 45′. The spring housing 43 threadedly interfaces with the valve retainer 46. The proximal side of the valve retainer 46 removably engages with a distal side 54′ of the mounting manifold 45′. This arrangement forms a distal support for the hydraulic control valve 20. Also, as noted, the mounting manifold midsection shoulder 57 engages the spring housing mid-section shoulder 55 which form a proximal support. The combination of the two supports removably locks the hydraulic control valve 20 to the mounting module 45′. Additionally, in the controlled environment embodiment, the hydraulic control valve 20 further includes an environmental seal 58 positioned to seal between the spring housing 43 and the mounting plate or module 45′. This is accomplished between the proximal and distal supports.

FIG. 6 schematically illustrates a hydraulic control valve system 220 that includes a hydraulic control valve 20, a removable mounting module 221, and a mounting assembly 40. As shown in FIGS. 1-3, the hydraulic control valve 20 has a valve body 21, the body 21 having a function port 26, a supply port 22 to allow for the supply of fluid to the function port 26, and a vent port 23 to allow fluid to vent from the function port 26. As shown in FIGS. 4A-B, the control valve 20 also has a gate assembly 170, the gate assembly 170 having a gate 171, a seal assembly 140, and a roller bearing assembly 172 including a roller bearing engagement plate 173 and an array of roller bearings 174 bearing against the roller bearing engagement plate 173. The seal assembly 140 includes a seal carrier 141 slidably mounted within the gate 171 and a shear seal 142, to selectively direct hydraulic pressure to and from the, e.g., subsea function by selectively alternating between a vent open-supply blocked position as shown in FIG. 4A and a vent closed-supply unblocked position as shown in FIG. 4B. In the illustrated embodiment, the configuration only includes one shear seal 142 for sealing of the supply port 22 and the vent port 23. Referring to FIGS. 2-3, the hydraulic control valve 20 also includes a valve actuation assembly 60 for slidably moving the seal assembly 140. In this instance, the valve actuation assembly 60 is in the form of a solenoid assembly and includes a female coupling assembly 201 integral with the hydraulic control valve body 21. This arrangement advantageously provides fluid pressure communication between the function output passage 199 and the internal valve cavity 27. The pressure switch or transmitter 150 is made integral to the valve 20.

As best shown in FIG. 6, the hydraulic control valve system 220 also includes a removable hydraulic mounting module 221. The mounting module 221 includes one or more control valves 20, an input-output module 222 to interface the module 221 to the control valve actuation assembly 60, and a mounting module housing 223 to mount the control valves 20. Preferably, the input-output module 222 includes a programmable logic controller 224 to selectably control individual valve positions, as shown in FIGS. 4A and 4B. Also referring to FIG. 3, the mounting module housing 223 is filled with a dielectric fluid 225 which is in fluid communication with the cavity 165 located between the conduit fitting 160, 160′ and valve actuation assembly 60. In the typical application of the hydraulic control valve removable module 221, the input-output assembly 222 and the hydraulic supply and vent lines for the hydraulic mounting module 221 interface with a subsea distribution unit which interfaces with a surface controller and surface hydraulic power unit.

The hydraulic control valve system 220 also includes the mounting assembly 40, which may be formed either separate or part of the removable module. The mounting assembly 40 includes a valve retainer 46 (retainer nut or ring or weld) for connecting the valve 20 to the mounting module 221, and an engagement assembly 225. The engagement assembly 225 connects the module 221 to the fixed base B having a function coupler C. The engagement assembly 225 compensates for a separation force generated by supply pressure between valve 20 and the function coupler 200. The engagement assembly 225 also includes a latch assembly 226 to releasably latch the removable hydraulic module 221 to the fixed base B.

In the hydraulic control valve system 220, the control valves 20 are placed in such a pattern inside the mounting module housing 223 as to connect directly to the mating hydraulic couplers C on the fixed base B, without the need for an additional interface manifold. Correspondingly, the fixed base side of the mounting module housing 223 has at least as many apertures or bores 227, shown schematically in FIG. 6 that allow the distal end 28 of the control valve 20 to protrude and be removably engaged with the fixed base side of the mounting module housing 223. Additionally, the hydraulic control valve system 220 configured in the control environment arrangement includes environmental seal 58 for each control valve 20 to provide a seal interface between the control valve 20 and the fixed base side of the mounting module housing 223. Note, in this embodiment, the fixed base B includes an array of male couplers C.

Exemplary operation for the hydraulic control valve system 220 in a power-on activated mode on a subsea platform is hereafter described. As shown in FIG. 6, the hydraulic control valve 20 is placed subsea and adjacent to, e.g., a production tree, and within a removable hydraulic mounting module 221 which is terminated to a fixed base structure B by means of a mechanical latch assembly 226. The removable hydraulic mounting module 221 may contain an input-output module 222 in the form of a one-atmosphere controller with modem or fiber optic signal interface depending on what type of control system is selected. Hydraulic supply S may feed into the module through hydraulic couplers C, shown schematically, located in the base B and the hydraulic valve including female coupler assembly 20 located the module shown schematically in FIG. 6. The coupler connection is made automatically upon the installation of the removable hydraulic mounting module 221. The supply is then routed to a bank (plurality) of hydraulic control valves 20 which are dedicated to operate an associated subsea function. Upon initiation of a signal from for example, the surface, the selected control valve 20 is actuated directing hydraulic supply pressure to the desired subsea function such as a tree gate valve. The control valve can then be deactivated which, in turn, will vent and close/deactivate the associated subsea function.

The hydraulic control valve 20 is placed inside the module housing 223 in a position to connect directly to the mating hydraulic coupler B on the fixed base B. The separation force generated by supply pressure between the valve 20 and the male coupler B is negated by the engagement assembly 225, typically a latch assembly 226, that holds the removable hydraulic mounting module 221 to the fixed base B. Also referring to FIGS. 2-3, the valve 20 is retained in position on mounting portion of the mounting module 221 by a valve retainer 46, typically a retainer ring or nut, which is thread onto the spring housing 43. The valve retainer 46 will combat the separation force induced by the hydraulic connection area and also allow the valve 20 to be removed from the inside of the mounting module 221, facilitating any wiring harness and hydraulic connections.

Also referring to FIGS. 4A and 4B, supply pressure is feed to the hydraulic control valve 20 via a seal disk 111′ which also routes the vented pressure from the valve 20. Where the valve actuation assembly 60 is in the form of a solenoid assembly, electric power is routed to the coil 68 from the input-output module 222, typically a CPU I/O Block or electrical interface depending on the control system type selected by the user. Once the signal to the input-output module 222 is received by the module 221, power is switched to the desired control valve 20 energizing the 68 coil. The coil 68 generates a magnetic field which moves the plunger or piston rod 61, thus pushing the gate 171 to the activated, vent blocked-supply open position as shown in FIG. 4B. The gate 171 will stop on the valve spring housing 43 aligning the shear seal 142 with the vent port 23. In this position the supply port 22 is open and the vent port 23 is capped or closed by the shear seal 142. Supply pressure will flood the interior of the valve (internal valve cavity 27) pressurizing the subsea function through the function coupler interface assembly 200. When the control valve 20 is to be closed, the electrical power is removed from the coil 68 thus allowing the gate return spring 101 to push the gate assembly 170 back to the default, vent open-supply blocked position as shown in FIG. 4A. In this position the gate 170 will hit and stop on the pressure housing 42 aligning the shear seal 142 with the supply port 22. The vent port 23 is now open and the supply port 22 is capped or closed by the shear seal 142. Function pressure will exit the valve 20 through the open vent port 23 and the associated header.

Mounted on the gate 171 is a seal carrier 141 which contains the shear seal 142. When the shear seal 142 is aligned with the supply port 22, supply pressure is feed through the shear seal 142 activating the radial seal 146 between the shear seal carrier 141 and the shear seal 142. Pressure acting on the differential area between the face of the shear seal 142 and the radial seal 146 will contain or block the supply, loading the gate 171 onto the opposing roller bearings 174 and tightening the seal between the shear seal 142 and the seal disk 111.

When the shear seal 142 is instead aligned with the vent port 23, supply pressure acting on the total shear seal radial area will force both the seal carrier 141 and the shear seal 142 against the seal disk 111 blocking the port. At this point there is nominal pressure inside the shear seal 142 so the roller bearings 174 will only receive the force generated by the seal carrier return spring 143.

Referring to FIGS. 2-3, if the hydraulic control valve 20 embodiment is one that includes a pressure switch or transmitter 150, the pressure switch or transmitter 150 will announce the presents of pressure via a signal when the valve 20 is opened. This signal can be used to verify the valve 20 has functioned properly and the desired subsea function has been activated. In addition, the hydraulic control valve 20 may contain a check valve 202, such as one including conical valve seal 204 in the function coupler assembly 200 that, for example, is mechanically opened when in contact with the mating coupler C on the fixed base B. This check valve 202 will limit sea water ingression during installation or removal of the valve package or module 221.

The hydraulic control valve 20 may be assembled according to a method whereby a gate assembly 170 is inserted through a distal end 176 of a pressure housing 42, and attaching a seal disk 111 through an aperture or bore 118 for in the pressure housing 42 to interface with the shear seal 142. In an embodiment, the gate assembly 170 includes a roller bearing assembly 172, a gate 171, a seal carrier 141, a sealed carrier return spring 143 biased with respect to the gate 171, and a shear seal 142. The method also includes connecting the distal bore 130 of the pressure housing 42 with the proximal end 133 of the spring housing 43 so as the gate assembly 170 engages, or abuts, a spring adapter 104 located within the spring housing 43. In an embodiment, the method further includes connecting a nonmagnetically responsive tube 65 to the proximal end 47 of the pressure housing 42, the tube 65 guidingly supporting a plunger or piston rod, 61. In an embodiment, the method further includes the steps of connecting a valve actuation assembly housing 41 to the proximal end 47 of the pressure housing 42. In an embodiment, the method includes connecting a pressure transducer, or switch, 150 and a pressure transducer or switch cap 77 to the proximal end 66 of the nonmagnetic steel tube 65 to allow a sealed exit for a pressure transducer or switch conductor 152. An embodiment also includes connecting a proximal end 133 of a spring housing 43 to the distal bore 130 of the pressure housing 42.

Referring to FIG. 6, a method for assembling a hydraulic control valve system includes providing a hydraulic control valve mounting module housing 223 having at least one aperture or bore 227, shown schematically in FIG. 6, for receiving a hydraulic control valve body 21. The method also includes inserting the distal end 28 of the control valve 20 through the at least one aperture 227, shown schematically in FIG. 6, and threading a valve retainer 46, nut or rim, to the hydraulic control valve body 21. The hydraulic control valve body 21 is adapted to receive a valve retainer 46 (nut or rim). The valve retainer 46 is used to secure the hydraulic control valve 20 to the control valve mounting module housing 223. In an embodiment, the valve retainer 46 is threadedly secured to the gate return spring housing 43. In an embodiment, the method further includes directly latching the module 221 to the fixed base B with no further interface couplings required between the hydraulic control valve 20 and the fixed base male couplers C.

Turning now to FIGS. 7 and 7A, there is shown an exemplary valve 300, in accordance with the present invention. The valve 300 is constructed and operates, except where outlined hereafter, as the valve 20 described earlier. In the valve 300, however, the solenoid-type valve actuation assembly 60 has been replaced by a hydraulic valve actuation assembly, generally indicated at 302. The hydraulic valve actuation assembly 302 includes a hydraulic fluid chamber 304 defined within actuator housing, or body, 306. The chamber 304 has a proximal end 308 and a distal end 310. The proximal end 308 is threaded to accommodate threaded attachment of hydraulic pilot pressure inflow line 312 and nut 160. The fluid chamber 304 includes a reduced-diameter distal portion 314 and an enlarged diameter proximal portion 316. A shoulder 318 is defined therebetween. A lateral vent port 320 extends from the hydraulic fluid chamber 304 through the housing 306 to vent line 125.

A hydraulic piston member 322 is reciprocally retained within the chamber 304. The piston 322 has a proximal end 324 and a distal end 326. Additionally, the piston 322 features a reduced diameter portion 328 and an enlarged diameter portion 330 which define a shoulder 332 therebetween. O-ring seals 334, 336 surround the piston member 322 to provide fluid sealing across portions of the piston member 322. It is noted that the cross-sectional area (i.e., the area that fluid pressure would act upon) presented by the distal end 326 and the smaller O-ring seal 336 is smaller than the cross-sectional area presented by the proximal end 324 and the larger O-ring seal 334. As seen in FIG. 7A, a chamber 338 is defined within the housing 306 between O-ring seals 334 and 336. The chamber 338, including the lateral side of the reduced diameter portion 328 of the piston member 322 and shoulder 332, is exposed to vent pressure via lateral port 320. The distal end 326 of the piston 322 abuts the gate 171.

In a preferred embodiment, a pressure monitoring port 340 is also disposed through the valve housing 306 and a pressure monitoring conduit 342 is secured to the valve body 21 so that pressure within the valve body 21 may be sensed and measured by a remote monitor (not shown) of a type known in the art. The pressure monitoring port 340 and conduit 342 may be used in place of the pressure switch/transducer 150 described earlier. The pressure monitoring function provides measurement of the pressure within the valve 300 as well as an indication of positive movement of the piston member 322 within the hydraulic chamber 304 and operation of the valve 300. The difference in internal valve pressure from a time when the valve is filled with supply pressure and when the valve 300 is vented is significant enough to provide a certain indication of valve state to a remote monitor.

Initially, the valve 300 is in the position shown in FIG. 7 with the shear seal 142 aligned with and blocking entrance of supply pressure through supply pressure port 22. In operation to actuate the valve 300, fluid pressure (i.e., the “pilot pressure”) is increased in the pilot pressure inflow line 312 to act upon the proximal end 324 and seal 334 of the piston member 322. The distal end 326 of the piston member 322 will urge the gate 171 to move distally so that the shear seal 142 is moved to block the vent port 23 and open the supply pressure port 22. When the supply pressure port 22 is unblocked, supply pressure will enter the valve housing 306 and flow to the function coupler interface assembly 200, as described earlier. The shoulder 332 of the piston member 322 will engage the shoulder 318 of the fluid chamber 304 to limit travel of the piston member 322 within the chamber 304.

When the pilot pressure entering the fluid chamber 304 from fluid inflow line 312 is decreased, the spring 101, together with function pressure and internal valve and vent pressure will urge the piston member 322 back to its original position with the vent port 23 open and supply pressure port 22 blocked. Fluid pressure within the valve body 21 and from the function coupler interface assembly 200 can be released via the vent port 23.

Advantageously, the construction of the hydraulic valve actuation assembly 302 permits lowers pilot pressures to actuate the valve 300. The smaller cross-sectional area of the distal end 326 and O-ring seal 336 is exposed to the internal valve pressure, thus reducing the pilot pressure required to operate the valve 300 by the size ratio of the two pressure-receiving areas. For example, if the size ratio between the larger proximal end 324/O-ring 334 and the smaller distal end 326/O-ring 336 is 2:1, and the valve 300 is operated with a 3000 psi supply pressure, then the pilot pressure required to operate the valve 300 will be approximately 1500 psi.

Additionally, if either of the O-ring seals 334 or 336 were to fail, fluid pressure would enter the chamber 338 that is defined between the two O-ring seals 334, 336. Because this chamber 338 is ported to the vent line 125, leaking fluid will pass to vent rather than becoming a harmful, controlling factor in the operation of the valve 300. Thus, the valve 300 provides a desirable protective feature in this regard. A typical application for a hydraulically actuated valve 300 would be in the instance of a short distance offset from a production facility or control station to an oil or gas well where the response time of the hydraulic pilot pressure (i.e., the time need for pressure variations to be transmitted along the pilot pressure inflow line 312) will not be a factor in operation. Alternatively, the valve 300 could be used in conjunction with an external solenoid valve (not shown) so that function out pressure is routed to and plumbed to the pilot pressure inflow line 312.

It is noted that valve 300 is preferably a non-interflow type valve. In other words, during operation of the valve 300 to move between a vent open-supply blocked position and a supply open-vent blocked position, or vice versa, there is no point at which both the vent port 23 and the supply port 22 are both partially opened due to the wall thickness of the shear seal 142, which is slightly larger than the supply or vent ports diameter 22, 23. There is, therefore, no opportunity for the supply pressure entering the valve 300 to be prematurely vented from the valve body 21, which might prevent complete operation of the subsea function. Thus, a non-interflow valve design is very desirable.

FIGS. 8 and 8A depict an alternative exemplary valve 400 having a segmented solenoid actuator assembly 402. The valve 400 is constructed and operates, in most respects, in the same manner as valve 20 described earlier. The segmented solenoid actuator assembly 402 includes an electromagnetic coil 68 that surrounds core assembly 404. An actuator assembly housing 406 surrounds and encloses the coil 68 and core assembly 404.

The core assembly 404 features a fixed core 408 having a longitudinal bore 410 formed within to accommodate stepped actuation rod 412. Additionally, the core assembly 404 includes a plurality of moveable core segments 414, 416, and 418 which are separated from each other and from the fixed core 408 by gaps 420, 422, and 424. It is noted that the moveable core segments 416 and 418 have bores 426, 428, respectively, disposed therethrough, while core segment 414 includes a blind bore 430 disposed therein. The stepped actuation rod 412 includes three axially connected rod portions 432, 434, 436 of progressively increasing diameter. The distal end 438 of the rod 412 pushes against the gate 171. The proximal end 440 of the rod 412 is disposed within the blind bore 430 of core segment 414. Additionally, the reduced diameter rod portion 432 is disposed through the bore 426 of the adjacent core segment 416 while the intermediate diameter rod portion 434 is disposed through the bore 428 of the core segment 418. Because the actuation rod 412 is stepped, it presents a pair of engagement shoulders 438, 440 that will engage the core segments 416, and 418 as they move toward the fixed core 408.

Prior to actuation, the valve 400 is in the position shown in FIG. 8 with the supply port 22 blocked and the vent port 23 open. To actuate the valve 400, the solenoid coil 68 is energized, in the same manner as described previously in connection with valve 20. When the coil 68 is energized, it creates a magnetic field that passes through the fixed core member 408 and moveable core segments 414, 416, 418 so that all of these are attracted to each other. The gaps 420, 422, and 424 are closed as the moveable core segments 414, 416, 418 are brought into contact with each other and with the fixed core member 408. The moveable core segment 418 will engage shoulder 440 of the actuation rod 412 as it moved toward the fixed core member 408. This action moves the actuation rod 412 and gate 171 in a distal direction. Also, the moveable core segment 416 will move toward the core segment 418 and, in so moving, will engage the shoulder 438 of the rod 412, thereby further urging the rod 412 and gate 171 in the distal direction toward its actuated position. Additionally, the core segment 414 will move toward the core segment 416 and, due to the seating of the rod 412 within the blind bore 430, will further urge the rod 412 and gate 171 distally to place the valve 400 in the actuated position. FIG. 8A depicts the valve 400 in an actuated position wherein the shear seal 142 now blocks the vent port 23 and open the supply pressure port 22. In this position, all of the core members 408, 414, 416, 418 are in contact with each other under influence of the magnetic field created by the coil 68.

A significant advantage of valve 400 is the reduced travel distance of magnetized components used to actuate the valve 400. The gaps 420, 422, 424 are small and the core segments are close together. The proximity of the components increases the effectiveness of the magnetic field used to actuate the valve since the effectiveness of magnetic attraction increase greatly as the distance between two magnetically attracted members is decreased. The actuation rod 412 is moved the total distance of all of the gaps 420, 422, and 424. For example, if the total amount of travel of the rod 412 is 0.156 inches, the gaps 420, 422, and 424 would each measure approximately 0.052″. As a result, the construction of the valve actuator assembly 402 assures more certain operation of the valve.

To move the valve 400 back to its original vent port open/supply port blocked position, the solenoid coil 68 is deenergized and the spring 101 urges the gate 171 in a proximal direction. Movement of the gate 171 will cause the actuation rod 412 to also move back to its original position.

FIGS. 9, 9A, 9B, and 9C depict a valve system 500 having a plurality of valves 502 mounted in a manifold 504. Although FIG. 9A illustrates a solenoid-actuated valve, it should be understood that the valves 502 may be actuated hydraulically or in other ways known in the art. The manifold 504 is used to provide supply fluid to the valves 502 and to carry away fluid that is vented from the valves 502. Because the general construction and operation of valve manifolds is well understood by those of skill in the art, such will not be described in detail herein. Generally, however, the manifold 504 includes an outer housing 506 having a valve seating plate 45′ and a manifold top plate 508 that is secured to the valve seating plate 45′ by a number of bolt-type connectors or welded. If weld type attachment is used then two top plates are desired one for the vent and one for the supply. 510. Function pressure is transmitted from the valve via the hydraulic coupler interface 502 through a fixed base 514 for operation of a subsea function (see FIG. 9A). Fluid transmission grooves 516 and 518 are formed into the valve seating plate or manifold top plate 45′ and, when the top plate 508 is secured over the top of the valve seating plate 45′, the grooves 516, 518 become enclosed spaces with the aid of seal rings if not welded 520. When so enclosed, the fluid transmission grooves 516, 518 form a control valve vent passage 516 and a control valve supply fluid passage 518, respectively. Fluid communication is provided from the passages 516 and 518 to supply port 22 and vent port 23. As FIG. 9 illustrates, the passages 516, 518 are annular and circumnavigate the valve seating plate 45′.

FIG. 9B illustrates an exemplary arrangement for the entry of supply fluid to the manifold 504, while FIG. 9C depicts an exemplary arrangement for removal of vent fluid from the manifold 504. Referring first to FIG. 9B, a hydraulic coupler 522 interconnects supply fluid inflow line 524 to the underside of the seating plate 45′. A fluid pathway 526 is defined within the top plate 508 and affixed filer 528 to carry supply fluid from the coupler 522 to annular fluid supply passage 516.

With respect to FIG. 9C, a fluid outflow line 532 is interconnected by hydraulic coupler 534 to the underside of seating plate 45′. A fluid pathway 536 defined within the seating plate 45′ allows fluid communication from the annular vent fluid passage 518 to the hydraulic coupler 534.

In operation, fluid is flowed into the manifold 504 via the inflow line 524 and is supplied to individual control valves 502, via the annular fluid supply passage 516 which are used to operate remote subsea functions. Fluid that is vented from the valves and subsea functions 502 enters the annular fluid vent passage 518 and then out through fluid outflow line 532.

A significant advantage of the fluid distribution arrangement of the valve system 500 is the reduction in cost and effort in creating the systems. Conventional valve systems and manfolds use a significant amount of tubing and conduits to transmit supply and vent fluids to and from the various valves within the manifold. Additionally, a large number of ports must be drilled through the manifold housing. The tubing and conduits must then be interconnected in a time consuming and expensive process. In accordance with this aspect of the present invention, the numerous conduits and ports are replaced by the annular fluid passages 516, 518.

With further reference to FIGS. 10, 10A, 10B, and 10C a further exemplary solenoid-actuated valve 502 is now described in greater detail. In many respect, the valve 502 is constructed and operates as the valve 20 described earlier, except where hereinafter explained. The valve 502 includes a valve body 21 that encloses a solenoid actuator assembly 550 and a differential piston assembly 552, both of which are operably associated with the gate 171 for selective movement thereof. An additional vent fluid passage 554 is defined within the seal disk 111 and enters the valve body 21 via hydraulic fitting 556 and port 558.

The solenoid actuator assembly 550 includes two electromagnetic coils 560, 562 that are disposed in a side-by-side relationship. The windings for the two coils 560, 562 run in opposite radial directions to provide for magnetic pull in opposing directions. Additionally, the actuator assembly 550 includes a pair of fixed core members 564, 566 and a moveable core member 568. Spacer rods 570 are secured between the two fixed core members 564, 566 and passes through the moveable core member 568. The moveable core member 568 is secured to an actuation rod 572 that passes through a bore 574 in the inboard fixed core member 566 and the differential piston assembly 552. At its distal end, the actuation rod 572 is affixed to the gate 171.

The differential piston assembly 552 includes a piston chamber 576 within which a differential area shuttle piston 578 is retained. The piston chamber 576 is ported to vent via port 558. A set of Belleville washers 580 is also disposed between the piston and the inboard fixed core 576. The washers are stacked on a reduced diameter portion 582 of the fixed core member 566. The shuttle piston 578 features a generally cylindrical body 584 having a radially enlarged distal portion 586 to define an annular shoulder 588. The body 584 has a central opening 590. The body 584 houses a plug retainer 592 and a compressible spring 594. The spring 594 is disposed between the plug retainer 592 and washers 580.

FIG. 9A illustrates exemplary power and control wiring for the valve 502. Power line 594 and sensor data line 596 extend from a remote power source (not shown) to pressure sensor assembly 598. Coil actuation wires and sensor data wires 600, 602 terminate within the valve pressure sensor assembly forming a junction box for all the valve wiring. This valve actuation system is pulse actuated as described previously with pulse defined as a surge of electrical power applied a given length of time then removed. After the electrical pulse is removed the valve will remain in the actuated position.

FIG. 10 shows the valve 502 in a closed position with the shear seal 142 blocking the supply pressure port 22. The vent port 23 is open, and the internal valve pressure is ambient. To actuate the valve 502 to an open position (shown in FIG. 10A), the outboard solenoid coil 560 is energized to draw the moveable core member 568 in a proximal direction and into contact with the fixed core member 564. Because the actuation rod 572 is affixed to the gate 171, the gate 171 is drawn proximally compressing the coil spring 594 until the shear seal 142 is blocking the vent port 23 and is not blocking the supply pressure port 22. Supply pressure enters the valve body 21 via supply pressure port 22 and is transmitted to the subsea function, as described previously.

FIG. 10B shows that the valve 502 remains open to provide supply pressure to the subsea function after the electrical power is removed. The differential piston assembly 552 assures that the valve 502 does remain open even though there is no power to energize the coils 600, 602. Supply pressure entering the valve body 21 from the supply port 22 and the receiving chamber 207 will act upon the enlarged distal portion 586 of the body 584. Fluid pressure behind the body 584 is a lower vent pressure due to the presence of port 558 proximate shoulder 588. Thus, the body 584 will move proximally and compress the washers 580, locking or holding the compression spring and gate in its current open position as shown in FIG. 10B. The gate 171 continues to block the vent port 23, allowing supply pressure to continue to flow from the supply pressure port 22 to the subsea function.

In the further event that supply pressure should be lost or drop below a certain value while the valve 502 is in the position shown in FIG. 10B, the valve 502 will automatically close. The spring force provided by the compressed washers 580 will overcome the reduced pressure within the valve body 21, push the piston forward, allowing the compression spring 594 to shift the gate 171 to a position where the shear seal 142 blocks the supply pressure port 22 and unblocks the vent port 23.

Additionally, the valve 502 may be shifted from the position shown in FIG. 10B to a supply pressure blocked/vent pressure opened position by energizing the inboard solenoid coil 562. This draws the moveable core member 568 into contact with the fixed inboard core member 566, as shown in FIG. 1C. This then moves the shear seal 142 to block the supply pressure port 22 and unblocks the vent port 23. It can be seen that the valve 502 may be positively opened and closed by pulsed commands from the controller 224. Additionally, the valve 502 provides for a “fail-safe close” in the event of loss or reduction of supply pressure. Pulse actuated, fail-safe close valves 502 are useful in situations where there is a great distance between the controller and the valve system 500 (i.e., 12 miles or so). Such a distance generally makes the use of hydraulic actuation infeasible due to the long response time. In an alternative embodiment, one could use fiber optic cables rather than electric cables for pulse communication from the multiplex controller 224 to the module 222. Pulse actuation is desirable because it allows multiple valves to be actuated one at a time without a large power requirement (could have conductors in the umbilical from surface of reasonable diameter/smaller number). Because power must be supplied from surface, this reduces costs for the system.

In the drawings and specification, there have been disclosed typical preferred embodiments of the invention, and although specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification, and as defined in the appended claims. 

1. A hydraulic control valve comprising: a) a valve body having a function port, a supply port to allow for the supply of hydraulic fluid to the function port, and a vent port to allow fluid to vent from the function port; b) a gate assembly having a gate moveably mounted within the valve body and a shear seal mounted within the gate, the gate assembly selectively directing hydraulic pressure to and from the function port by selectively alternating between a vent open-supply closed position and a vent closed-supply open position; and c) a valve actuation assembly for moving the gate and shear seal between the positions.
 2. The hydraulic control valve of claim 1 wherein the valve actuation assembly comprises a hydraulic actuation assembly having: a) a hydraulic fluid chamber with an associated hydraulic fluid inflow line; b) a hydraulic piston member retained within the chamber and moveable between distal and proximal positions in response to changes in pressure from the fluid inflow line; and c) an actuation member extending between the piston member and the gate assembly to selectively move the gate assembly between said vent open-supply closed position and vent closed-supply open position.
 3. The hydraulic control valve of claim 2 wherein the piston member presents distal and proximal pressure-receiving areas, the distal pressure receiving area being smaller than the proximal pressure-receiving area.
 4. The hydraulic control valve of claim 2 further comprising a fluid passage interconnected with the hydraulic fluid chamber to provide vent pressure to a portion of the fluid chamber.
 5. The hydraulic control valve of claim 4 further comprising a pair of annular fluid seals upon said piston member to define a vent-ported chamber therebetween.
 6. The hydraulic control valve of claim 1 wherein the valve actuation assembly comprises a solenoid actuator assembly that is operably associated with the gate for selective movement of the gate.
 7. The hydraulic control valve of claim 6 wherein the solenoid actuator assembly comprises: a) a solenoid coil; b) a fixed core element within the coil; c) a plurality of moveable core elements within the coil and axially moveable therewithin, each of the moveable core elements being moveable with respect to the fixed core element and selectively engageable with an actuation member to cause movement of the gate.
 8. The hydraulic control valve of claim 7 wherein the actuation member further comprises a stepped actuation rod having multiple rod portions of different diameters, at least one of the rod portions presenting a shoulder to engage a moveable core element.
 9. The hydraulic control valve of claim 7 further comprising a pressure sensor assembly used as a wiring junction point where all wiring including the coil(s) and the pressure sensor are interconnected, as required, and terminated for connection to an external control source.
 10. The hydraulic control valve of claim 6 wherein the solenoid actuator assembly comprises: a) a moveable core element; b) first and second independently energizeable solenoid coils, the first coil being selectively energizable to move the core element in a proximal direction, the second coil being selectively energizable to move the core element in a distal direction.
 11. The hydraulic control valve of claim 10 wherein the first and second coils have windings in opposite radial directions.
 12. The hydraulic control valve of claim 10 wherein the solenoid actuator assembly further comprises a pair of fixed core elements, each of which are located proximate an opposite axial end of the moveable core element to provide magnetic attraction to the moveable core element.
 13. A hydraulic control valve comprising: a) a valve body having a function port, a supply port to allow for the supply of hydraulic fluid to the function port, and a vent port to allow fluid to vent from the function port; b) a gate assembly having a gate moveably mounted within the valve body and a shear seal mounted within the gate, the gate assembly selectively directing hydraulic pressure to and from the function port by selectively alternating between a vent open-supply closed position and a vent closed-supply open position; c) a valve actuation assembly for moving the gate and shear seal between the positions; and d) a fail safe mechanism for allowing electrical pulse actuation to retain the valve in the vent closed-supply open position when electrical power is removed and further allow the valve to fail safe close upon loss of supply pressure.
 14. The hydraulic control valve of claim 13 wherein the fail safe mechanism comprises a differential piston assembly disposed between the valve actuation assembly and the gate assembly and comprising: a) a differential piston chamber that is ported to vent; b) a differential area shuttle piston moveably retained within the differential piston chamber and having: 1) a body that presents a distal portion upon which supply pressure is applied and a radial shoulder that is exposed to vent pressure; and 2) a compressible portion that allows the body to be moved within the chamber in response to supply pressure.
 15. The hydraulic control valve of claim 14 wherein the compressible solenoid actuated portion comprises a compressible spring.
 16. The hydraulic control valve of claim 14 wherein the internal valve pressure activated compressible locking or holding portion comprises a Belleville washer.
 17. The hydraulic control valve of claim 13 wherein the valve actuation assembly is controlled by electrical pulses provided by a remote controller, said electrical pulses being operable to move the valve between the vent open-supply closed position and the vent closed-supply open position.
 18. A valve system comprising: a) a manifold with at least one valve operably associated therewith that utilizes hydraulic fluid; b) the manifold further having a first plate member and a second plate member being affixed to one another; and c) a hydraulic fluid communication system having at least one fluid pathway formed by an groove in at least one of the plate members for transmission of hydraulic fluid to or from the valve.
 19. The valve system of claim 18 wherein the hydraulic fluid communication system further comprises: a) a first annular groove operably associated with a fluid inflow line and the valve for supply of hydraulic fluid to the valve; and b) a second annular groove operably associated with a fluid outflow line. 